Thyrwort: a thick, fibrous plant common in the northeastern Nibenay. The root is cut into slices which are dried into leathery disks, usually stringed together with twine. When chewed, it acts as a potent stimulant. It is normal to see laborers, dockworkers, soldiers, etc. in the Nibenay chewing on bits of thyrwort during their work - often the same piece for hours on end. The practice is considered unhygienic by the upper classes. While thyrwort has few ill effects (save for staining teeth and gum infection) it is somewhat addictive. "White" thyrwort is considered safe, but rare strains of "red" thyrwort, infected by a kind of fungus, can cause the user to experience strange delusions and insomnia.

Siyat: a tobacco-like plant cultivated everywhere in Cyrodiil, but especially in Colovia. The leaves can be dried and smoked in siyat-pipes. Colovians make a kind of cigar from them. Smoking siyat is considered relaxing and invigorating. A common diversion with no known ill effects, besides a risk of addiction.

Indulcet: an expensive drug harvested from luminous algae native to Blackwood and the Topal Bay mangrove forests. It appears as a kind of luminous white pearls, and tastes salty and bitter. Can be consumed raw or pickled in vinegar. Indulcet produces a sense of overwhelming serenity, relaxes the body and the mind, and enhances creativity and appreciation of music and the arts. Some believe it increases virility. Often used by artists and by those who wish to commune with the saints and spirits. Dibellan cults are especially fond of it. Overdoses can lead to spasms and a loss of motor control.

Somnalius: a mangrove fern common to the southern Nibenay and the Ruma Floodlands. The fronds, when pulped, act as a sedative. Somnalius tea is often used as a sleeping aid, but it can also be eaten or smoked in a waterpipe for increased effect. Some cults fashion it in a kind of incense: people under the influence of somnalius smoke become more receptive to suggestions and ideas. Excessive dosages have been linked to cases of mass psychosis and hallucinations.

Sursum: a kind of mold, commonly found in humid, dark places in the eastern jungles. A cheap lower-class drug, sometimes cultivated in "mold pots". Can be consumed raw or in a dried, powdery version: it is sometimes snorted or smoked, but addicts tend to take the raw mold and rub it on their skin or, in extreme cases, in open wounds. Very popular among laborers, pit fighters, and beggars in the Heartlands. Sursum clouds the mind, but gives a boost in endurance and strength, suppressing feelings of hunger, physical or emotional distress. Prolonged use can lead to permanent nerve damage and gangrene.

Aegrotat: a processed alchemical substance which causes sensations of euphoria and innocence when consumed. Several variations exist, using a mix of Nibenese marsh plants. Some are less reliable than others, and finding a safe producer can be hazardous. Aegrotat looks like a waxy, honey-colored substance, which must be heated and vaporized in a specially designed lamp. Edible versions exist, but are less popular. An expensive drug, in vogue with Heartlander aesthetes, decadent poets, assassins and the more fashionable death-cults. Although various medicinal qualities are attributed to it, Aegrotat is mainly known for causing a sense of bliss and, oddly improving speed and reaction time. Prolonged use causes a mental indifference to the real world, as the user is lost in internal reveries.

Nux Vomica: more poison than drug, this substance is made from the seeds of the strychnos tree, soaked and boiled in milk to produce a consumable extract. It appears as a milk-like substance, usually in small, decorated bottles. Despite its toxicity, Nux Vomica is praised as a kind of panacea against the dangers of Imperial politics: it is said to dispel common diseases, poisons, and other occupational hazards of Heartlands intrigue. Daily purges with Nux Vomica are something of a health craze among Heartlands plutocrats fearing poison or venereal diseases. Common side-effects are anxiety, memory problems, dizziness, and vomiting. Prolonged use weakens the blood and can lead to digestion problems or liver failure.

Incarnadine: also called "godsblood", this pinkish mineral-infused water is said to seep from the ground within Blood Dome Temples. The Templars believe this to be a miracle of Tiber Septim, who blessed the ground of the Empire with his blood on these places. Drinking the liquid causes a kind of trance, in which the user is easily provoked to extreme violence. The Templars, who use the substance in their battle-rituals, believe it helps them commune with the Divine Tiber Septim and allows them to mimic his Breath powers, although this has never been observed.

Quaesto Vil: a rare, expensive and dangerous compound of marsh herbs and rice wine, infused by the spirit of a serpentine Daedra which inhabits the bottle. An ink-black, viscous fluid consumed by drinking it or with eye-drops. Bottles are often equipped with a built-in eyedropper. Quaesto Vil leads to enhanced awareness, sensations and cases short, visceral hallucinations and nightmares. Some believe it can be used to predict the future, though most likely these visions are views into the realm of Vaernima. Very popular among fortune-tellers and Vaernimite cults. Prolonged use can cause the user to experience visions even without consuming the liquid, leading to paranoia, panic attacks, and insomnia. The visions increase in length and frequency, until the addict can no longer perceive the difference between the real world and the nightmare. Wild rumors claim that people can be physically assaulted by things they see in their dreams.

Pyrrhic Acid: a rare and dangerous substance, refined from a mineral outwash from certain geysers in the Marshes of Mir. The curious volcanic activity of this region is known to bring to the surface rare salts and alchemical fumes. Purified from its imperfections, Pyrrhic Acid causes intense feelings of joy, psychosis, and a loss of contact with reality. It is extremely addictive over even short periods of use, and drastically cuts down the user's life expectancy either through its acidity, or through self-inflicted wounds.